The present invention provides a heating element for use within a smoking device which is intended to beheld in the lips of a consumer, and in which burning does not take place. More particularly, this invention relates to an electrically-powered heating element having a plurality of discrete electrically resistive heating segments, only one of which is active at any given time. The element is intended to heat a flavor-generating medium, which is contained within the device, without burning. As a result of this heating, the flavor-generating medium produces a flavored aerosol or vapor which the consumer may inhale.
Previously known conventional smoking devices deliver flavor and aroma to the user as a result of combustion. During combustion, a mass of combustible material, primarily tobacco, is oxidized as the result of applied heat (typical combustion temperatures in a conventional cigarette are in excess of 800.degree. C. during puffing). During this heating, inefficient oxidation of the combustible material takes place and yields various distillation and pyrolysis products. As these products are drawn through the body of the smoking device toward the mouth of the user, they cool and condense to form an aerosol or vapor which gives the consumer the flavor and aroma associated with smoking.
Such conventional smoking devices have various perceived drawbacks associated with them. Among these is the production of sidestream smoke which may be objectionable to non-smokers in the vicinity of the consumer of the device.
An alternative to conventional smoking devices are those in which the combustible material itself does not directly provide the flavorants to the aerosol or vapor inhaled by the user. In these devices, a combustible heating element, typically carbonaceous in nature, is ignited and used to heat air which is then drawn through a zone which contains some means for producing a flavored aerosol or vapor upon interaction with the heated air. While this type of smoking device produces little or no sidestream smoke, it still shares some characteristics with conventional cigarettes which are perceived as undesirable.
In both the conventional and carbon element heated smoking devices described above combustion takes place during their use. This process naturally gives rise to many by-products as the material supporting the combustion breaks down and interacts with the surrounding atmosphere.
Additionally, the combustion process which takes place in both of the aforementioned types of smoking devices cannot be easily suspended by the user in order to allow storage of the smoking device for later consumption. Obviously a conventional cigarette may be extinguished prior to its being smoked to completion, but if the user wishes to save the remaining portion of the cigarette for later use, he is faced with the problem of storing a relatively small, ash laden paper tube; convenient storage for such an item would most likely not be readily available. Users of the carbon element heated combustible smoking devices do not even have the option of extinguishing the device after it has been ignited, as the heating element contained within such devices is typically inaccessible to the user. Once lit, such carbon element smoking devices must be smoked to completion or discarded prior to completion while still burning.
Accordingly, it is the object of the present invention to provide for an electrically-powered heating element for use within an article intended to be held in the lips of a consumer, which will heat a flavor-generating medium without burning. This flavor-generating medium, as a result of the heating, would produce a flavored aerosol or vapor which the consumer could then inhale. Furthermore, the heating element disclosed is configured so as to allow the consumer to operate the device in a puff by puff manner, with the option of suspending the operation of the device after any given puff, prior to the depletion of the device. The device could then be conveniently stored until some later time at which the consumer wished to resume operation.